This invention relates to a circumferential clamp and a latching assembly.
It is known to use circumferential clamps to secure axially aligned parts together, for example high pressure and high temperature ducting in engine bleed systems. Circumferential clamp couplings typically comprise a pair of hinged jaws which clamp about respective flanges at the ends of the parts to be clamped together. The jaws are secured together at their free ends by a latch, for example fastener such as a bolt pivotally mounted to one of the jaws which latches over the end of the opposite jaw. Once latched, the jaws are clamped together by tightening the latch. In safety critical applications it is often necessary to provide a redundant latch to keep the clamp closed in the event of failure of the primary fastener. The redundant latch is disposed adjacent to and radially outward (with respect to the center of the clamp) of the primary fastener. This arrangement is bulky and occupies a large amount of radial space outwardly of the clamp. Furthermore, the moment generated by the radially outer redundant latch about the center of the clamp is greater than that of the primary latch, and so produces high stresses in the clamp. A further disadvantage associated with this arrangement is that it is possible to access, and so further tighten, the redundant fastener once the primary fastener has been tightened with the consequence that the fasteners can be alternately tightened putting progressively more stress into the coupling.